JP6349834B2 - Display body, display body manufacturing method, and labeled article - Google Patents

Description

  The present invention relates to a display body, a manufacturing method of the display body, and an article with a label which prevent counterfeiting by attaching a display body to the article or the like.

Display with a visual effect different from that of ordinary printed materials for the purpose of preventing counterfeiting of securities such as gift certificates and checks, cards such as credit cards, cash cards, ID cards, and certificates such as passports and licenses There is a technique of sticking and crimping the surface of a certificate such as securities or a card in the form of a transfer foil or a sticker.
In addition, the distribution of counterfeit goods has become a social problem for articles other than securities and certificates, and the chances of applying the same anti-counterfeiting technology to such articles are increasing.

Examples of anti-counterfeiting techniques include micro characters, special light emitting ink, watermarks, diffraction gratings, holograms, and the like. These anti-counterfeiting techniques can be roughly divided into two. One is a counterfeit measure that determines authenticity using a verification device such as a simple device or measuring device, and the other is a counterfeit measure that can be easily determined by the naked eye.
As anti-counterfeiting technology, various fine structures are produced by an electron beam drawing apparatus (EB apparatus), and a security device that can be differentiated from similar techniques by visual observation has been developed. The most common security device is a surface relief type diffraction grating (see, for example, Patent Document 1).

JP 2003-295744 A

A diffraction grating as described in Patent Document 1 has a more complicated structure than a general printed matter, and it is difficult to produce the diffraction grating without a high fine processing technique.
However, recently, silver and iridescent similar products similar to surface relief type diffraction gratings have been distributed, and the anti-counterfeiting effect has diminished, so that counterfeiting has a new optical characteristic that replaces diffraction gratings. It is desired to provide a security device with excellent prevention.
The present invention is intended to solve such problems, and controls the spectrum of specular reflection light while maintaining the diffraction effect of the surface relief type diffraction grating, and can be distinguished from counterfeit products. The object is to provide a body, a method for manufacturing a display body, and a labeled article.

One embodiment of the present invention includes a concavo-convex structure region in which a concavo-convex structure including a plurality of concave portions and a plurality of convex portions is provided on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The light reflecting layer is a display body which is laminated on the concave portion or the convex portion.
One embodiment of the present invention includes a concavo-convex structure region in which a concavo-convex structure including a plurality of concave portions and a plurality of convex portions is provided on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The light reflecting layer is composed of a plurality of layers,
Each of the plurality of layers is a display body in which the concave portion and the convex portion are laminated in different shapes.

Another embodiment of the present invention is the display body in which the plurality of layers have different spectral reflectance characteristics.
Another embodiment of the present invention is a display body in which one of the plurality of layers has a spectral reflectance characteristic corresponding to a preset color image.
Another embodiment of the present invention is the display body in which each of the plurality of layers is formed of a different metal material.
Another embodiment of the present invention is a display body in which the uneven structure region is a diffraction grating.
Another embodiment of the present invention is the display body, wherein the light reflecting layer is formed of aluminum.

Another embodiment of the present invention is an article in which the display body described above includes a light-transmitting base material or an article including a base material that does not transmit light, with a light-transmitting adhesive layer interposed therebetween. It is the article with a label characterized by being attached and formed.
One embodiment of the present invention is a concavo-convex structure region forming step of forming a concavo-convex structure region in which a concavo-convex structure including a plurality of concave portions and a plurality of convex portions is provided on at least a part of one surface of the light transmission layer;
A first light reflecting layer laminating step of laminating a first light reflecting layer on the concave portion or the convex portion provided in the concave and convex structure region formed in the concave and convex structure region forming step;
A method of manufacturing a display body, comprising: a concavo-convex structure removing step of partially removing the concavo-convex structure region formed in the concavo-convex structure region forming step as a subsequent step of the first light reflecting layer laminating step. is there.

One embodiment of the present invention is a concavo-convex structure region forming step of forming a concavo-convex structure region in which a concavo-convex structure including a plurality of concave portions and a plurality of convex portions is provided on at least a part of one surface of the light transmission layer;
A first light reflecting layer laminating step of laminating a first light reflecting layer on the concave portion or the convex portion provided in the concave and convex structure region formed in the concave and convex structure region forming step;
As a post-process of the first light reflecting layer stacking step, the concavo-convex structure removing step for partially removing the concavo-convex structure region formed in the concavo-convex structure region forming step,
And a second light reflecting layer laminating step of selectively laminating a second light reflecting layer on the concave and convex portions provided in the concave and convex structure region partially removed in the concave and convex structure removing step. It is the manufacturing method of the display body which makes it.

Another embodiment of the present invention is the method for manufacturing a display body, wherein the first light reflection layer and the second light reflection layer have different spectral reflectance characteristics.
In one embodiment of the present invention, the spectral reflectance characteristic of the first light reflecting layer or the second light reflecting layer is a spectral reflectance characteristic corresponding to a preset color image. It is a manufacturing method.
Another embodiment of the present invention is the method for manufacturing a display body, wherein the first light reflection layer and the second light reflection layer are formed of different metal materials.
One embodiment of the present invention is the method for manufacturing a display body, wherein at least one of the first light reflection layer and the second light reflection layer is formed of aluminum.
Another embodiment of the present invention is a method for manufacturing a display body, wherein the uneven structure region is a diffraction grating.

  According to one embodiment of the present invention, it is possible to control a spectrum of specularly reflected light while maintaining the diffraction effect of a surface relief type diffraction grating, and to distinguish it from a counterfeit product.

It is a top view explaining the schematic structure of the display body of 1st embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is a perspective view which expands and shows an example of the structure employable as a 1st uneven structure area | region. FIG. 3 is an enlarged view of a region A shown in FIG. It is a perspective view which expands and shows an example of the structure employable as a 2nd uneven structure area | region. FIG. 3 is an enlarged view of a region B shown in FIG. 2. FIG. 3 is an enlarged view of a region C shown in FIG. 2. It is the figure which observed the display body from the front side. It is a figure which shows the reflective transmittance | permeability of a metal thin film. It is a figure which shows roughly a mode that an uneven | corrugated structure area | region emits a diffracted light. It is a figure which shows a mode that the illumination light was entered into the display body and the diffracted light of the uneven structure area | region was observed. It is a figure which shows the image obtained when illuminating light is entered from the opposite side of an observer and observed. It is the figure which showed in detail the transmission principle of illumination light. It is a top view which shows roughly an example of the card | curd which made the goods support the stripe transfer foil for forgery prevention. It is the XV-XV sectional view taken on the line of FIG. It is a figure which shows the manufacturing method of a display body. It is a figure which shows an uneven | corrugated structure removal process.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
Hereinafter, a first embodiment of the present invention (hereinafter referred to as the present embodiment) will be described with reference to the drawings.
(Configuration of display body 10)
As shown in FIGS. 1 and 2, the display body 10 includes a light transmission layer 11, a light reflection layer 13, and an adhesive layer 15. In FIG. 2, as an example, a case where the light transmission layer 11 side is arranged on the front side (observer side) and the adhesive layer 15 side is arranged on the back side is shown.

The light transmission layer 11 protects the concavo-convex structure 14 from dirt and scratches on the surface, thereby achieving the effect of maintaining the visual effect of the display body 10 over a long period of time. Furthermore, the light transmission layer 11 makes the reproduction difficult by not exposing the uneven structure 14.
As a material constituting the light transmission layer 11, for example, a resin having a light transmission property can be used. Examples of the light-transmitting resin include polyethylene terephthalate, polyethylene naphthalate, polycarbonate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, nitrocellulose, polyethylene, polypropylene, acrylic styrene copolymer, vinyl chloride, and polymethyl methacrylate. Thermosetting resins such as polyimide, polyamide, polyester urethane, acrylic urethane, epoxy urethane, silicone, epoxy, melamine resin, etc., and various acrylic monomers, epoxy acrylates, urethanes that are UV or electron beam curable Use oligomers such as acrylates and polyester acrylates, reactive polymers such as acrylics and epoxies with acrylic and methacrylic groups, and cellulosic resins. It is possible.

In addition, as a structure of the light transmission layer 11, you may employ | adopt the structure of two or more layers in consideration of surface strength, the ease of forming the uneven structure 14, etc.
The light reflecting layer 13 plays a role of increasing the reflectance of the interface where the concavo-convex structure 14 is provided.
As a material which comprises the light reflection layer 13, it is possible to use metal materials, such as aluminum, silver, tin, chromium, nickel, copper, gold | metal | money, and those alloys, for example.
Moreover, as a material which comprises the light reflection layer 13, you may use the material which consists of material from which a refractive index differs from the material which comprises the light transmissive layer 11, such as a dielectric material, for example.

The light reflecting layer 13 can be formed by using a vacuum film forming method. As the vacuum film forming method, a vacuum deposition method, a sputtering method, or the like is applicable.
The adhesive layer 15 is formed on the light reflection layer 13 or the light transmission layer 11. In the present embodiment, as an example, a case where the adhesive layer 15 is formed on the light reflecting layer 13 as shown in FIG. 2 will be described.
Further, the adhesive layer 15 is provided for attaching the display body 10 to an article to be subjected to forgery prevention measures.
In addition, the configuration of the adhesive layer 15 includes two or more layers in consideration of the adhesive strength between the article to be counterfeited and the display 10 and the smoothness of the adhesive surface of the article to be counterfeited. It is good. 2 shows a configuration in which the display body 10 is observed from the light transmission layer 11 side, a configuration in which the display body 10 is observed from the light reflection layer 13 side may be employed.

Next, the concavo-convex structure 14 provided at the interface between the light transmission layer 11 and the light reflection layer 13 will be described.
At the interface (boundary surface, main surface) between the light transmission layer 11 and the light reflection layer 13, there are a first uneven structure region 12a, a second uneven structure region 12b, a third uneven structure region 12c, and a flat region 12e. Is formed.
The first concavo-convex structure region 12a, the second concavo-convex structure region 12b, and the third concavo-convex structure region 12c are provided with at least one of a plurality of concave portions and a plurality of convex portions. That is, each of the first uneven structure region 12a, the second uneven structure region 12b, and the third uneven structure region 12c has the uneven structure 14. More specifically, the first uneven structure region 12a, the second uneven structure region 12b, and the third uneven structure region 12c have a diffractive structure.
When forming the concavo-convex structure 14 included in the first concavo-convex structure region 12a, the second concavo-convex structure region 12b, and the third concavo-convex structure region 12c at the interface between the light transmission layer 11 and the light reflection layer 13, for example, Then, after producing the original plate with an electron beam drawing apparatus or a laser drawing machine, a metal plate is produced by electroforming or the like. And it is possible to use the method of forming the uneven structure 14 on a film by thermocompression-bonding the produced metal plate on a predetermined film.

As shown in FIG. 3, the first concavo-convex structure region 12a is provided with a diffraction grating formed by arranging a plurality of concavo-convex structures 14a.
The term “diffraction grating” means a structure that generates a diffracted wave when irradiated with illumination light such as natural light. In the following description, a portion sandwiched between the convex portions of the diffraction grating may be referred to as a “concave portion”.
The center-to-center distance between adjacent concavo-convex structures 14a is, for example, in the range of 200 nm to 2000 nm. In the present embodiment, as an example, a case where the center-to-center distance between adjacent concavo-convex structures 14a is 2000 nm will be described.

The height of the concavo-convex structure 14a is in the range of 100 nm to 500 nm. In the present embodiment, a case where the height of the concavo-convex structure 14a is 200 nm will be described as an example.
Further, as shown in FIG. 4, the concavo-convex structure 14a of the first concavo-convex structure region 12a is formed by laminating a first light reflecting layer 13a and a second light reflecting layer 13b. In the example shown in FIG. 4, the first light reflecting layer 13 a and the second light reflecting layer 13 b are laminated, but the uneven structure 14 a is not limited to this, and the first light reflecting layer 13 a, Alternatively, only one of the second light reflecting layers 13b may be stacked.

In the present embodiment, as an example, a case where the concavo-convex structure 14a of the first concavo-convex structure region 12a is a two-dimensional concavo-convex structure will be described. However, the configuration of the concavo-convex structure 14a is not limited to this, and the pillars A three-dimensional concavo-convex structure in which are arranged may be employed.
The concavo-convex structure 14b included in the second concavo-convex structure region 12b is a structure obtained by removing the first concavo-convex structure region 12a as shown in FIG. Specifically, the concavo-convex structure 14b included in the second concavo-convex structure region 12b has a structure in which the first concavo-convex structure region 12a is removed by 100 nm. In addition, although not particularly illustrated, the concavo-convex structure 14 included in the third concavo-convex structure region 12c is similarly a structure in which the first concavo-convex structure region 12a is removed.

The concavo-convex structure 14b included in the second concavo-convex structure region 12b may be arranged in parallel to a straight line that intersects the X axis and the Y axis at an angle of 45 degrees.
In addition, the center distance D between adjacent concavo-convex structures 14b is, for example, in a range of 200 nm to 2000 nm. The height of the concavo-convex structure 14b is, for example, in the range of 100 nm to 500 nm. In addition, although not particularly illustrated, the uneven structure 14 included in the third uneven structure region 12c is similarly configured such that the center-to-center distance between adjacent uneven structures 14 is within a range of, for example, 200 nm to 2000 nm, and the height of the uneven structure 14. Is, for example, in the range of not less than 100 nm and not more than 500 nm.

The reason why the center-to-center distance between adjacent concavo-convex structures 14 is set to the above value is that it becomes difficult to form the concavo-convex structure 14 when the center-to-center distance between adjacent concavo-convex structures 14 is shortened. Therefore, the distance between the centers of adjacent concavo-convex structures 14 is set to 200 nm or more.
The reason for setting the height of the concavo-convex structure 14 to the above value is that it becomes difficult to form the concavo-convex structure 14 as the height of the concavo-convex structure 14 increases. Therefore, the height of the concavo-convex structure 14 is set to 500 nm or less.
The reason why the distance between the centers of adjacent concavo-convex structures 14 and the height of the concavo-convex structure 14 is set to the above values is that when the depth of the concavo-convex structure 14 increases, it becomes difficult to form the concavo-convex structure 14. It is. Therefore, the aspect ratio (height / center distance) of the concavo-convex structure 14 is set to 2 or less.

As shown in FIG. 6, the concavo-convex structure 14b of the second concavo-convex structure region 12b is formed by laminating the first light reflecting layer 13a only on the convex portion 16a. That is, in the concavo-convex structure 14b of the second concavo-convex structure region 12b, as shown in FIG. 6, the first light reflecting layer 13a is not laminated on the concave portions 16b other than the convex portions 16a.
In the concavo-convex structure 14c of the third concavo-convex structure region 12c, as shown in FIG. 7, the first light reflection layer 13a is laminated only on the convex portion 16a, and the second light reflection layer 13b is bonded to the light transmission layer 11. It is formed by being laminated on all the interfaces of the layer 15. Thus, when the concavo-convex structure 14 in which the first light reflecting layer 13a and the second light reflecting layer 13b are laminated is enlarged and observed from the observer side, the first light reflecting layer 13a and the second light reflecting layer 13b are alternately arranged. Looks like it is in place.

Further, as shown in FIG. 8A, the first light reflecting layer 13a can be confirmed in an image obtained by magnifying and observing the first concavo-convex structure region 12a from the observer side. However, in the image obtained by magnifying the concavo-convex structure region 12a from the viewer side, the second light reflection layer 13b cannot be observed because it is on the back side of the first light reflection layer 13a.
Further, as shown in FIG. 8B, in the image obtained by magnifying and observing the second concavo-convex structure region 12b from the observer side, the first light reflecting layers 13a and the adhesive layers 15 are alternately arranged. It is possible to confirm.

Further, as shown in FIG. 8C, the first light reflecting layer 13a and the second light reflecting layer 13b are alternately arranged in the image obtained by magnifying and observing the third uneven structure region 12c from the observer side. It is possible to confirm in the state.
The flat region 12e is a flat surface. Since the optical performance expressed by the flat region 12e is different from the optical performance expressed by the first concavo-convex structure region 12a, the second concavo-convex structure region 12b, and the third concavo-convex structure region 12c, by incorporating the flat region 12e, It is possible to improve the design. However, a configuration without the flat region 12e may be employed.

As described above, the display body 10 of the present embodiment includes an interface provided with at least one of the second uneven structure region 12b and the third uneven structure region 12c. In the second concavo-convex structure region 12b, the first light reflecting layer 13a is laminated only on the convex portion 16a. Further, in the third uneven structure region 12c, different light reflecting layers 13 are laminated at the concave portion 16b and the convex portion 16a.
Therefore, it is difficult for the display body 10 of the present embodiment to accurately analyze the uneven structure 14. In addition, even if the uneven structure 14 is analyzed, it is difficult to reproduce the light reflecting layer 13 laminated on the uneven structure 14 in the display body 10 of the present embodiment, and thus it is difficult to replicate.

In addition, the display body 10 of the present embodiment has a special visual effect. That is, the first concavo-convex structure region 12a generates diffracted light with wavelength dispersion, and thus appears to be color-shifted to seven colors depending on the viewpoint position, and is recognized as an interface on which a diffraction grating is formed. Further, also in the second concavo-convex structure region 12b, diffracted light accompanied by wavelength dispersion is generated and appears to be color-shifted to seven colors depending on the viewpoint position, and is recognized as an interface where a diffraction grating is formed.
Therefore, the first concavo-convex structure region 12a and the second concavo-convex structure region 12b recognize that a person who attempts forgery or imitation has the same concavo-convex structure at first glance. However, when transmission observation is performed, the first uneven structure region 12a and the second uneven structure region 12b have completely different optical characteristics. Here, in the transmission observation, in general, the display body 10 is irradiated with light from a light source arranged on the light reflection layer 13 side, and the state of the surface of the display body 10 is observed by transmitted light from the surface of the display body 10. It is to be.

Observation of transmitted light by transmission observation is possible only in the second concavo-convex structure region 12b. Therefore, not only design expression by reflection observation but also design expression by transmission observation becomes possible. Here, the reflection observation generally refers to irradiating light on the surface of the display body 10 from a light source arranged above, and observing the state of the surface of the display body 10 with reflected light from the surface of the display body 10. is there.
Further, in the display body 10 of the present embodiment, the third uneven structure region 12c generates diffracted light with wavelength dispersion in the same manner as the first uneven structure region 12a and the second uneven structure region 12b. The color shift appears to be recognized as an interface on which a diffraction grating is formed. However, when observing Nagara and regular reflection light, a color obtained by adding the colors perceived by the first light reflection layer 13a and the second light reflection layer 13b is observed. The reason why the colors are added in this way is that the first light reflection layer 13a and the second light reflection layer 13b are laminated very finely and alternately every 2000 nm. It cannot be perceived. That is, it is a juxtaposed color mixture state, and an intermediate color between the first light reflecting layer 13a and the second light reflecting layer 13b is perceived.

The film thicknesses of the first light reflecting layer 13a and the second light reflecting layer 13b are preferably in the range of 30 nm or more and 90 nm or less from the viewpoint of optical characteristics.
This is because, when the film thickness of the first light reflection layer 13a and the second light reflection layer 13b is less than 30 nm, for example, as shown in FIG. 9, the transmitted light exceeds 50%. This is because the contrast of the first uneven structure region 12a and the second uneven structure region 12b is lowered.
Moreover, when the film thickness of the 1st light reflection layer 13a and the 2nd light reflection layer 13b exceeds 90 nm, as shown in FIG. 9, for example, the 1st light reflection layer 13a and the 2nd light reflection layer 13b This is because the variation value of the transmittance with respect to the film thickness becomes small. Therefore, even if the first light reflecting layer 13a and the second light reflecting layer 13b are laminated with a film thickness exceeding 90 nm, the change in the optical effect is small, so the first light reflecting layer 13a on the slope of the concavo-convex structure 14 The film thickness of the second light reflecting layer 13b is set within the range of 30 nm or more and 90 nm or less from the optical characteristics. In the present embodiment, as an example, a case where the film thickness of the first light reflecting layer 13a and the second light reflecting layer 13b is 90 nm will be described.

Further, the transmittance during the transmission observation of the second uneven structure region 12b is controlled by the area ratio when the protrusions 16a and the recesses 16b of the second uneven structure region 12b are observed from the vertical direction. Is possible.
Furthermore, the second concavo-convex structure region 12b controls the transmittance during transmission observation by laminating the first light reflecting layer 13a only on the convex portion 16a of the concavo-convex structure 14. Therefore, the diffracted light emission region (second concavo-convex structure region 12b) in the reflection observation and the transmission region in the transmission observation substantially coincide with each other. In reflection observation, diffracted light is observed from the portion where the first light reflection layer 13a is laminated on the concavo-convex structure 14b. In transmission observation, the first light reflection layer 13a in the concavo-convex structure 14b is observed. A portion where no is laminated is observed through light. That is, in reflection observation and transmission observation, the observed image has a negative and positive relationship.
Therefore, when the display body 10 of this embodiment is used as a forgery prevention medium, a high forgery prevention effect can be obtained.

Hereinafter, the visual effect of the display body 10 of the present embodiment will be described in more detail.
First, the visual effect resulting from the uneven structure 14a of the first uneven structure region 12a will be described.
When the illumination light is irradiated onto the diffraction grating, the diffraction grating emits strong diffracted light in a specific direction as shown in FIG. 10 with respect to the traveling direction of the illumination light that is incident light. In FIG. 10, the diffraction grating is denoted by reference numeral “12d”, the incident light is denoted by reference numeral “31a”, the zeroth-order diffracted light among the diffracted lights is denoted by “32a”, and the first-order diffracted light among the diffracted lights. Is denoted by reference numeral “33a”.
The most representative diffracted light is the first-order diffracted light 33a.

The emission angle β of the first-order diffracted light 33a can be calculated from the following formula (1) when the light travels in a plane perpendicular to the grating line of the diffraction grating.
d = λ / (sin α−sin β) (1)
In Equation (1), d represents the grating constant of the diffraction grating, and λ represents the wavelengths of incident light and diffracted light. Α represents the exit angle of 0th-order diffracted light, that is, transmitted light or specularly reflected light. Therefore, the absolute value of α is equal to the incident angle of the illumination light, and the incident angle is symmetric with respect to the Z axis (in the case of a reflective diffraction grating). For α and β, the clockwise direction from the Z axis is the positive direction.
Further, as apparent from Equation (1), the emission angle β of the first-order diffracted light 33a changes according to the wavelength λ. That is, the diffraction grating has a function as a spectroscope. Accordingly, when the illumination light is white light, the color perceived by the observer changes when the observation angle is changed in a plane perpendicular to the grating line of the diffraction grating.

In addition, the color perceived by the observer under a certain observation condition changes according to the lattice constant d. For example, it is assumed that the diffraction grating emits first-order diffracted light in the normal direction. That is, the emission angle β of the first-order diffracted light 33a is assumed to be 0 °. Then, if the observer perceives the first-order diffracted light 33a, and the emission angle of the 0th-order diffracted light 32a at this time is αN, Equation (1) can be simplified to Equation (2) below. Is possible.
d = λ / sin αN (2)
As is clear from the equation (2), in order to make the observer perceive a specific color, the wavelength λ corresponding to the color, the incident angle | αN | of the illumination light, and the lattice constant d are expressed by the equation ( What is necessary is just to set so that the relationship shown in 2) may be satisfied. For example, white light including all light components having a wavelength in the range of 400 nm to 700 nm is used as illumination light, the incident angle | αN | of the illumination light is set to 45 °, and the spatial frequency (lattice constant) It is assumed that a diffraction grating in which the reciprocal number is distributed within a range of 1000 lines / mm to 1800 lines / mm is used. In this case, when the diffraction grating is observed from the normal direction, a portion having a spatial frequency of about 1600 lines / mm looks blue and a portion having a spatial frequency of about 1100 lines / mm looks red.

Note that the diffraction grating is easier to form when the spatial frequency is smaller. Therefore, in a normal display body, the majority of diffraction gratings are diffraction gratings having a spatial frequency in the range of 500 lines / mm to 1600 lines / mm.
As described above, the color perceived by the observer under a certain observation condition can be controlled by the grating constant d (or spatial frequency) of the diffraction grating. When the observation angle is changed from the previous observation condition, the color perceived by the observer changes.
In the above description, it is assumed that light travels in a plane perpendicular to the grid lines. When the diffraction grating is rotated around the normal line from this state, the effective value of the grating constant d changes according to the rotation angle with respect to a certain observation direction. As a result, the color perceived by the observer changes. That is, when a plurality of diffraction gratings having only different grating line orientations are arranged, different colors can be displayed on the diffraction gratings. Further, when the rotation angle becomes sufficiently large, diffracted light cannot be recognized from a certain observation direction, and is recognized in the same manner as when there is no diffraction grating.

Further, when the height of the concavo-convex structure 14a constituting the diffraction grating is increased, the diffraction efficiency changes (depending on the wavelength of illumination light and the like). When the area ratio of the diffraction grating to the pixel described later is increased, the intensity of the diffracted light is further increased.
Accordingly, when a plurality of pixels in which the concavo-convex structure 14a is arranged in a predetermined arrangement pattern is arranged in the first concavo-convex structure region 12a, the concavo-convex structure is formed by a part of the pixels and the other part. When at least one of the spatial frequency and orientation of 14a is made different, it becomes possible to display different colors on those pixels and to set observable conditions.

Then, at least one of the height of the concavo-convex structure 14a and the area ratio of the diffraction grating with respect to at least one of the pixels is made different between a part of the pixels constituting the first concavo-convex structure region 12a and the other part. Thus, the luminance of these pixels can be made different. Therefore, by using these, it is possible to display images such as full-color images and stereoscopic images in the first concavo-convex structure region 12a.
The “image” means an image that can be observed as a spatial distribution of at least one of color and luminance. The “image” includes a photograph, a figure, a picture, a character, a symbol, and the like.

In addition, the diffracted light 305 of the first uneven structure region 12a is observed as an image as shown in FIG. In FIG. 11, the light source is indicated by reference numeral “302”, the observer is indicated by reference numeral “303”, and the incident light is indicated by reference numeral “304”.
An image when the display 10 is observed through transmission is as shown in FIG. In FIG. 12, the light source is indicated by reference numeral “302”, the observer is indicated by reference numeral “303”, and the incident light is indicated by reference numeral “304”.

As shown in FIG. 12, the first concavo-convex structure region 12a and the third concavo-convex structure region 12c cannot observe the transmitted light 307 during transmission observation. As described above, this is because the light is blocked by the second light reflecting layer 13b because the second light reflecting layer 13b is uniformly laminated on the concavo-convex structure 14.
In addition, the behavior of light when transmitted through the second concavo-convex structure region 12b is as shown in FIG. As described above, the first light reflecting layer 13a is laminated on the convex portion 16a. Therefore, the light is shielded by the first light reflection layer 13a, but the light is transmitted because the first light reflection layer 13a is not laminated on the concave portion 16b. Therefore, the second concavo-convex structure region 12b has a watermark effect.

The uneven structure 14 of the display body 10 has a wave shape. That is, the area ratio (aperture ratio) between the region where the light reflecting layer 13 is present and the region where the light reflecting layer 13 is not present is changed by cutting the structure while moving in the Z-axis direction. That is, the amount of transmitted light can be controlled by the depth at which the uneven structure 14 is removed.
In order to increase the amount of transmitted light, the depth at which the concavo-convex structure 14 is removed is increased. Further, in order to reduce the amount of transmitted light, the depth for removing the concavo-convex structure 14 is reduced. Thus, the aperture ratio can be changed by controlling the depth at which the concavo-convex structure 14 is removed.
Thus, since the aperture ratio may be changed by removing the concavo-convex structure 14, the amount of transmitted light can also be controlled by changing the concavo-convex structure 14 to a cone shape, a triangular pyramid shape, or changing the pitch. Is possible. That is, it is possible to control the amount of transmitted light according to the shape of the concavo-convex structure 14 while keeping the depth at which the concavo-convex structure 14 is removed constant. Thus, the transmitted light quantity can be controlled by controlling the depth of removal of the concavo-convex structure 14 or changing the shape of the concavo-convex structure 14.

Further, since the amount of transmitted light can be controlled by the shape of the concavo-convex structure 14, the resolution can be controlled in units of the concavo-convex structure 14, and high resolution can be achieved. Therefore, gradation, micro characters, etc. can be expressed, and the design can be improved.
Further, when the first light reflecting layer 13a and the second light reflecting layer 13b are made of a metal material, as shown below, by adopting a method of partially removing the metal, further forgery prevention effect is improved. Can be achieved.

Hereinafter, the partial metal removal method will be described.
In the first method, washing ink is printed in a negative pattern on a substrate, and a metal reflection layer (first light reflection layer 13a, second light reflection layer 13b is formed on the entire surface by vapor deposition or sputtering. ), The printed portion is washed away with water to remove the metal reflection layer (the first light reflection layer 13a and the second light reflection layer 13b) and form a pattern. It is a method using processing.
In the second method, a mask agent is printed in a positive pattern on the metal reflection layer (first light reflection layer 13a, second light reflection layer 13b), and a portion not printed with the mask agent is corroded with a corrosive agent. Thus, an etching process for forming a pattern is used.

A third method is to apply a strong laser to a portion of the metal reflection layer (first light reflection layer 13a, second light reflection layer 13b) to be removed to apply a metal reflection layer (first light reflection layer 13a, second light reflection layer 13b). This is a method using laser processing to form a pattern by selectively destroying the reflective layer 13b).
The display body 10 of the present embodiment can be used as, for example, a seal label, a thread, a stripe transfer foil, a spot transfer foil or the like having an anti-counterfeit effect.
Moreover, since the display body 10 of this embodiment is difficult to counterfeit or imitate, forgery and imitation become difficult when the display body 10 of this embodiment is supported by an article. Moreover, since the display body 10 of this embodiment has the visual effect mentioned above, it is also easy to discriminate | determine the articles | goods in which it is unknown whether it is a genuine article between a genuine article and a non-authentic article. .

(Composition of labeled items)
Hereinafter, the configuration of an article (an article with a label) that supports the display body 10 of the present embodiment will be described.
In the present embodiment, as an example, a case will be described in which the labeled article is a card 40 shown in FIG. 14 formed by supporting an anti-counterfeit stripe transfer foil (display body 10) on the article.
The card 40 includes a transparent plastic substrate 44, and a printed layer 41 is formed on the plastic substrate 44.
Further, the display body 10 is affixed to the card 40 as an anti-counterfeit stripe transfer foil.

The display body 10 is formed with a relief type diffraction grating.
Further, the display body 10 removes the concavo-convex structure after the first concavo-convex structure region 12a is deposited, and further removes the concavo-convex structure 14 after the deposition of the second concavo-convex structure region 12b and the first concavo-convex structure region 12a. The third concavo-convex structure region 12c and the flat region 12e are formed.
In the first uneven structure region 12a, an aluminum reflective layer (light reflective layer 13) is uniformly laminated, and in the second uneven structure region 12b, an aluminum reflective layer (light reflective layer 13) is formed on the convex portion, and copper is formed on the concave portion. The reflective layer (light reflective layer 13) is laminated. In addition, an aluminum reflective layer (light reflective layer 13) is selectively stacked on the third uneven structure region 12c.

The distance between the centers of the first uneven structure region 12a is 1000 nm, and the depth of the uneven structure 14a is 200 nm.
Further, as shown in FIG. 15, the display 10 includes a surface protective layer / peeling layer 42, a light transmission layer 11, a first light reflection layer 13a (aluminum reflection layer or copper reflection layer), The second light reflection layer 13b (aluminum reflection layer or copper reflection layer), the adhesive layer 15, and the plastic substrate 44 are laminated. In the example shown in FIG. 15, the surface protective layer / peeling layer 42 side is the front side, and the plastic substrate 44 side is the back side.

The interface between the light transmission layer 11 and the first light reflection layer 13a or the second light reflection layer 13b is the first uneven structure region 12a, the second uneven structure region 12b, the third uneven structure region 12c, and the flat region 12e. Is included.
Since the card 40 includes the display body 10, when the regular reflection light of the first uneven structure region 12a, the second uneven structure region 12b, and the third uneven structure region 12c of the card 40 is observed, In the concavo-convex structure region 12a and the second concavo-convex structure region 12b, a color expressed by the spectral reflectance of aluminum is perceived. On the other hand, the third uneven structure region 12c is made of aluminum and copper, and the first light reflection layer 13a and the second light reflection layer 13b are formed. Therefore, a color obtained by adding the respective spectral reflectances is perceived.

Therefore, when the regular reflection light of the first uneven structure region 12a, the second uneven structure region 12b, and the third uneven structure region 12c is observed, the optical characteristics are completely different. However, when diffracted light is observed, the first concavo-convex structure region 12a, the second concavo-convex structure region 12b, the second concavo-convex structure region 12b, and the third concavo-convex structure region 12b are separated by spectroscopy using the first concavo-convex structure region 12b, the second concavo-convex structure region 12c, The third concavo-convex structure region 12c appears to shine in rainbow colors. As a result, it is possible to create a latent image pattern in which the moon mark appears only when specular reflection light is observed.
That is, it is possible to determine authenticity by changing the image when observing diffracted light and when observing specularly reflected light. In addition, the color perceived by regular reflection light is the sum of the spectral reflectances of aluminum and copper. Therefore, since the two light reflecting layers 13 (the first light reflecting layer 13a and the second light reflecting layer 13b) can exhibit specific optical characteristics, the forgery prevention effect is enhanced. Further, when the card 40 is observed through the transmission, it is possible to observe the transmitted light only in the third uneven structure region 12c. For this reason, it is possible to change an image that can be observed in reflection observation and transmission observation, and it is possible to improve the forgery prevention effect.

(Manufacturing method of the display body 10)
Next, the manufacturing method of the display body 10 is demonstrated.
As shown in FIG. 16, the manufacturing method of the display body 10 includes a concavo-convex structure region forming step, a first light reflecting layer stacking step, a concavo-convex structure removing step, and a second light reflecting layer stacking step.
The concavo-convex structure region forming step is a step of forming the concavo-convex structure 14 on one surface of the light transmission layer 11 as shown in FIG.
The first light reflecting layer laminating step is a step subsequent to the concavo-convex structure region forming step, and is a step of laminating the first light reflecting layer 13a on the concavo-convex structure 14, as shown in FIG.
In the first light reflecting layer stacking step, the first light reflecting layer 13a is stacked on the concavo-convex structure 14 by a vacuum deposition method.
The concavo-convex structure removing step is a step subsequent to the first light reflecting layer laminating step, and is a step of partially removing the concavo-convex structure 14 as shown in FIG.

Further, in the concavo-convex structure removing step, for example, as shown in FIG. 17, the concavo-convex structure 14 (workpiece) is placed on a flat table called a lapping machine 35, and between the lapping machine 35 and the workpiece removal surface. In addition, the lapping agent 30 is sandwiched as abrasive grains, and the workpiece is removed by sliding in a state where pressure is applied (pressurized) from above.
The second light reflecting layer stacking step is a subsequent step of the concavo-convex structure removing step. As shown in FIG. 16D, the second light reflecting layer 13b is formed on the concavo-convex structure 14 partially removed in the concavo-convex structure removing step. Is a step of laminating.
In the second light reflecting layer laminating step, the second light reflecting layer 13b is laminated on the concavo-convex structure 14 partially removed in the concavo-convex structure removing step by vacuum deposition.
As described above, in the method for manufacturing the display body 10 according to the present embodiment, the plurality of light reflection layers 13 (first light reflection layer 13a and second light reflection layer 13b) are selectively stacked on the concave portions 16b and the convex portions 16a. To do.

(Effects of the first embodiment)
The effects of this embodiment are listed below.
(1) Since the light reflecting layer is laminated on the concave or convex portion of the concavo-convex structure on one surface of the light transmitting layer, negative and positive images can be obtained by reflection observation and transmission observation. In addition, the reflectance and transmittance can be controlled by changing the ratio of the concave and convex portions of the concave-convex structure.
(2) Since different light reflecting layers are laminated on the concave and convex portions of the concavo-convex structure on one surface of the light transmission layer, the specular reflection light is a combination of each color of the reflective material laminated on the concave and convex portions. It is visible to humans. Therefore, it is possible to control the color of the regular reflection light of the light reflection layer by changing the reflective material.

(3) By adding a concavo-convex structure removing step for partially removing the concavo-convex structure region to the concavo-convex structure region forming step and the first light reflecting layer laminating step, the light reflecting layer is laminated only on one of the concave portion or the convex portion. Is possible.
(4) A plurality of light reflecting layers can be obtained by adding a concavo-convex structure removing step and a second light reflecting layer laminating step to partially remove the concavo-convex structure region to the concavo-convex structure region forming step and the first light reflecting layer laminating step. Can be selectively stacked on the concave and convex portions.
(5) Since the concavo-convex structure is a diffraction grating, incident light can be diffracted, and design properties that cannot be expressed by printing can be imparted.
(6) By stacking materials having different spectral reflectance characteristics of the light reflecting layer on the concave and convex portions, it becomes possible to express an intermediate color between the colors of the respective light reflecting layers.

(7) Since one of the spectral reflectance characteristics of the light reflecting layer laminated on the concave portion or convex portion corresponds to a color image set (prepared) in advance, it is possible to enhance the design and anti-counterfeit effect. is there.
(8) Since the light reflecting layer is formed of two types of materials, the number of steps can be simplified as compared with a display body using a plurality of types of light reflecting layers.
(9) Since the concave portion or the convex portion of the light reflecting layer is made of aluminum, it is possible to increase the diffraction rate of the diffracted light and to reduce the cost of the display body.
(10) By attaching the display body to an article made of a light-transmitting base material or an article made of a base material having no light transmittance, it is possible to impart a high forgery prevention effect to the article.

  DESCRIPTION OF SYMBOLS 10 ... Display body, 11 ... Light transmission layer, 12a ... 1st uneven structure area | region, 12b ... 2nd uneven structure area | region, 12c ... 3rd uneven structure area | region, 12d ... Diffraction grating, 12e ... Flat area | region, 13 ... Light reflection layer , 13a ... first light reflecting layer, 13b ... second light reflecting layer, 14a-14c ... concavo-convex structure, 15 ... adhesive layer, 16a ... convex part, 16b ... concave part, 30 ... lapping agent, 31a ... incident light, 32a ... 0th order diffracted light, 33a ... 1st order diffracted light, 35 ... lapping machine, 40 ... card, 41 ... printed layer, 42 ... surface protective layer / peeling layer, 44 ... plastic substrate, 302 ... light source, 303 ... observer, 304 ... Incident light, 305 ... Diffracted light, 307 ... Transmitted light

Claims (15)

A concavo-convex structure region provided with a concavo-convex structure composed of a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The display body, wherein the light reflecting layer is laminated only on the convex portion. A concavo-convex structure region provided with a concavo-convex structure composed of a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The light reflecting layer is composed of a plurality of layers,
One layer of the plurality of layers is stacked only on the convex portion, and the other layer of the plurality of layers is stacked on the concave portion and the convex portion ,
Wherein the plurality of layers, respectively, display body spectral reflectance characteristics are characterized by different of Rukoto. A concavo-convex structure region provided with a concavo-convex structure composed of a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The light reflecting layer is composed of a plurality of layers,
One layer of the plurality of layers is stacked only on the convex portion, and the other layer of the plurality of layers is stacked on the concave portion and the convex portion,
Each of the plurality of layers is formed of a different metal material . A concavo-convex structure region provided with a concavo-convex structure composed of a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer,
A light reflecting layer is provided in the uneven structure region,
The light reflecting layer is composed of a plurality of layers,
One layer of the plurality of layers is stacked only on the convex portion, and the other layer of the plurality of layers is stacked on the concave portion and the convex portion,
Each of the plurality of layers is formed of a different metal material and has a different spectral reflectance characteristic . One of said plurality of layers, any one of the preceding claims 2, characterized in that the color corresponding to the color image set in advance is formed of a metal having a spectral reflectance perceived Display body described in 1.   The display body according to claim 1, wherein the uneven structure region is a diffraction grating.   The display body according to any one of claims 1 to 6, wherein one of the plurality of layers is formed of aluminum.   The display body according to any one of claims 1 to 7 has light transmittance on an article including a base material having optical transparency or an article including a base material not having optical transparency. An article with a label, characterized in that the article is attached through an adhesive layer. A concavo-convex structure region forming step of forming a concavo-convex structure region provided with a concavo-convex structure comprising a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer;
A first light reflecting layer laminating step of laminating a first light reflecting layer only on the convex portion of the concave portion and the convex portion provided in the concave and convex structure region formed in the concave and convex structure region forming step;
The manufacturing method of the display body characterized by including the uneven | corrugated structure removal process of removing partially the uneven | corrugated structure area | region formed at the said uneven | corrugated structure area | region formation process as a post process of said 1st light reflection layer lamination process. A concavo-convex structure region forming step of forming a concavo-convex structure region provided with a concavo-convex structure comprising a plurality of concave portions and a plurality of convex portions on at least a part of one surface of the light transmission layer;
A first light reflecting layer laminating step of laminating a first light reflecting layer on the concave portion or the convex portion provided in the concave and convex structure region formed in the concave and convex structure region forming step;
As a post-process of the first light reflecting layer stacking step, the concavo-convex structure removing step for partially removing the concavo-convex structure region formed in the concavo-convex structure region forming step,
And a second light reflecting layer laminating step of selectively laminating a second light reflecting layer on the concave and convex portions provided in the concave and convex structure region partially removed in the concave and convex structure removing step. A method of manufacturing a display body.   The method for manufacturing a display body according to claim 10, wherein the first light reflection layer and the second light reflection layer have different spectral reflectance characteristics.   The said 1st light reflection layer or said 2nd light reflection layer is formed with the metal which has the spectral reflectance in which the color corresponding to the color image set beforehand is perceived. 11. A method for producing the display body described in item 11.   The said 1st light reflection layer and said 2nd light reflection layer are each formed with a different metal material, The manufacture of the display body of any one of Claims 10-12 characterized by the above-mentioned. Method.   14. The display body manufacturing method according to claim 10, wherein at least one of the first light reflecting layer and the second light reflecting layer is formed of aluminum. Method.   The method for manufacturing a display body according to any one of claims 9 to 14, wherein the uneven structure region is a diffraction grating.

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